Heated portable spray gun



Spt- 2 1947- A. s. PITRE Er Al. 2,426,641

l HEATED PORTABLE SPRAY GUN Ema Aug. s, 194s ANTQNIO PITRE, THEODORE ILLAVER,

HILTON NALOOF ROBERT L.RO0ERS.

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Patented Sept. 2, 1947 mmm PORTABLE SPRAY GUN Antonio S. Pitre, United States Navy, Theodore M. Lauer, Vallcio, Milton Malooi, Santa Rosa, and

Robert L. Rogers, Oakland, Calif.

o Application August 9, 1943, SerialNo. 497,988 Y I3 Claims. (01.91-44') v l(Granted under the .act of March 3, 1883, as

amended April 30, 1928; 370 0. G. 757) I'his invention relates to a device for controlling 'the flow of material non-fluid at atmospheric temperatures and more specifically, to a gun for high-melting-point materials.

In general, it is an object of the invention to provide a device which is simple of construction, and quickly and readily manufactured of inexpensive common materials, which may be repaired by workmen at the place of operation. and which may be used with ease, safety and economy. y

Another object is to provide a gun for highmelting-point materials such as hot plastic paints; and to provide such a gun in which the material delivered does not harden or, if the materfal does harden, which may be put to further use without being dismantled.

Another object is to provide a gun for hotV plastic paints, which gun is suitable for the application of such paints in cramped quarters.

Other objects of the invention will, in part, be obvious, and will, in part, appear hereinafter.

The invention accordingly comprises articles of manufacture possessing the features, properties and relation of elements that will be exemplied in the' articles hereinafter described, the scope of the application of which will be indicatedin the claims.

For a'better understanding of the invention, reference should be had to the following de scription taken in connection with the drawing in which Fig. 1 is a. side view in elevation, partly in section, and partly broken away, of a device embodying one form of the invention; and

Fig. 2 is a view, in section, the plane of sec- The surfaces defining the few open spaces are' close together and accessible only with difficulty.

Although this presented a situation where spray rather than brush was obviously called for, still,

because of the large size of the only guns to be had, practically all paintingl on submarines has had to be done by hand with a brush-this.4 detion being indicated by the line 2-2 of Fig. l,

of the device shown in Fig. 1.,

Guns for spraying materials above the at- A mospherlc temperature of application have been subject to two important drawbacks. One was that from time to time, and for various reasons, the material to be delivered solidified .in the gun. If the workman had to-lay vit down, the chances were that after a moment it would be found frozen,? the valve'could not be moved and the nozzlewas solid. In northern latitudes this occurred so often as to make such guns unusable as a matter of practice.

'Ihe other main drawback was that portable guns that could spray high-melting-point plastics or plastic paints were so large that on that account their use in certain elds of application was absolutely prohibited. In submarines, for example, space is filled wherever possible.

spite the fact that paint applied by brush added five more tons of paint to a normal sizepresentday submarine than spraying would have'required, and brush-applied paint is thicker, more brittle, has relatively poor adherence, and flakes worse. The adherence of paint in some instances is of vital importance. In a submarine, examplia gratia, flakes of paint must never be allowed to get into trim lines, strainers, trim pumps, or drain pumps because, if these latterbecome clogged with the flakes, the boat becomes incapable of divingv or surfacing. lAs a result, certain submarine surfaces had to go unpainted, although they could have been reached by hand, because hand brushing gave later aking and there was no gun that could deliver hot paint and that was small enough to be manipulated near the surfaces to be painted. Furthermore, .the interiors of submarines sent to northern waters hadto go' without repainting no matter how badly they needed it, because it is impossible to brush on high-melting paintsagainst cold metal.

The present gun does not have the above mentioned disadvantages. It is available at all latitudes. It is being used on the surfaces of all spaces that a hand can reach with a brush. It. applies' a hot paint which does not ake. It is being used on submarines, both exterior .and interior surfaces. `Also,.it does not freeze.l

In the drawing, I0 denotes a gun barrel or conduit means having therethrough a conduit I2, which enters on the underside near the discharge end and leav'es axially at the frontend. A nozzle I4 may be attached to the barrel to ,deliver the material from the conduit. A valve means or mechanism I6 is attached to the bottom of the barrel, and thev end of a pasageway I8, through the mechanism, registers with the entrance of conduit i2.` In the embodiment shown, an in` ternally threaded tube depends from the lbarrel lli, and the valve mechanism is screwed therein. The opening and closing valve element 20 is movable axially toward and from the valve seat Spring 24 tends to keep element 2li seated 22. and the valve closed. The stem 26 of valve element. 20 is pivotally connected to trigger 28 as by a pin or the like which yis pivotally attached to the barrel IllV as by a pin or' the like. 'I'he trigger and handle 30, which are substantially at a right angle 'to the barrel, can be grasped in one hand. The handle is preferably removably secured to the barrel as by means of a screw, with a retaining pin, as shown, to prevent turning...

The pivot pins or thellke may be removed, and the valve means i 6 may be readily unscrewed and detached from the barrel, when desired.

Means are provided which supply suillcient y'heat to maintain the material in the nomle, barrel and valve in fluid condition, and these may be of any convenient type. The means shown comprise a resistance coil unit 32 wound around the barrel l0. The coil is separated from the preferably metallic barrel by insulation 34 and-is covered by a removable casing 38,. It is desirable that the unit be capable of maintaining the material passing through the gun ata temperature oi at least 400 F. as there are coatings which do not adhere properly when applied at lower temperatures, although they may be .iluid h at somewhat lower temperatures. One end of heating unit 32 may be connected to the metallic valve I6 which may be connected to the heating element in the delivery tube described in the Patent No. 2,377,899 dated 12 June 1945, to Ari-- tonio S. Pitre and Earl Wilson for improvements in conduits. Or said one end may be connected directly to oneA side oi a potential source.

The material is delivered into the opening It from a suitable supply source, through a flexible delivery tube, such for example, as is described in the aforementioned patent.

'Ihe heating and valve. units are not linearly` positioned in the direction'of spray but are placed said conduit and external to said barrel means,

purposes without the payment of any royalties thereon or therefor.

What we claim as new and desire toisecure Letters Patent for is:

1. A portable, manually operable gun for delivering a material which does not flow at atmospheric temperature, said gun comprising grip.

means, barrel`means extending from said grip means and having a conduit enteringfand adapted for conducting material through the end of' said barrel means, valve means in communication with said conduit and external to said barrel means, andheating means associated'with said barrel means for heating by conduction contents 'of said conduit and said valve means, said valve means being demountable independently of said heating means.

2. A portable, manually Doperable gun for delivering a material which does not ilow at atmospheric temperature, said gun comprising grip means, barrel means extending from said grip means and having a conduit entering, and adaptedfor conducting material through the end of, said barrel means, valve means in communicationlwith said conduit and external to said barrel means, and heating means associated with said barrelmeans for heating by conduction contentsof said conduit and-said valve means, f and trigger means near said .grip means, sail'lv andiheating means associated with said barrel means for heating by conduction contents of said conduit and said valve means, said valve means being demountable.independently of saidl heating means.

ANTONIO s. PITRE. THEODORE M. LAUER. NnLTON MALOOE. ROBERT L. ROGERS.

REFERENCES' CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Kovanda et al. .---1- Sept. 13, 1927 

